smooth coast

例句：

1. 1. The surfaceof the lake is very smooth.
   湖的表面非常光滑。
2. 2. The car's paint jobis smooth and shiny.
   这辆车的漆面光滑且光亮。
3. 3. The floor was smoothand polished to perfection.
   地板光滑且打磨得完美无瑕。